Current Pharmaceutical Design - Volume 24, Issue 33, 2018

Background: The most common form of dementia is Alzheimer's disease (AD), which is characterized, in part, by the accumulation of neurofibrillary tangles (NFT), followed by synaptic and neuronal loss. NFTs are mainly composed of aggregated hyperphosphorylated Tau. It has been demonstrated that pathological concentrations of zinc induce 1] activation of a major Tau kinase – the glycogen synthase kinase-3β (GSK-3β), and 2] promote Tau aggregation and toxicity. Activity-dependent neuroprotective protein (ADNP) and its derived peptide NAP exhibit neuroprotective properties against a variety of toxic insults, including toxic zinc concentrations. ADNP deficiency results in increased content of the GSK-3β active form, Tau hyperphosphorylation and NFTlike structure formation, all of which have been prevented by NAP treatment. Our previous experiments showed that NAP enhanced Tau-microtubule association in the face of zinc toxicity. Interestingly, NAP protection against zinc toxicity was rescued by Tau overexpression in NIH-3T3 fibroblast cells, which naturally does not express high amounts of Tau. Objectives and Methods: Pheochromocytoma cells (PC12), exposed to high concentration of zinc (400μM), were used to determine the protective effect of NAP on Tau phosphorylation and two Tau kinases (Fyn and GSK-3β). Knockdown of Tau expression in PC12 cells by RNA silencing was used to determine Tau's requirement for the NAP protective activity under zinc intoxication. Results: NAP treatment attenuated Tau hyperphosphorylation and GSK-3β increased activity caused by zinc intoxication. Furthermore, Tau knockdown completely abolished NAP protective activity. Conclusion: These results together with the previous findings strongly corroborated Tau's involvement in NAP/ADNP cellular activity.

Pituitary adenylyl cyclase activating polypeptide (PACAP) is a neuropeptide with great neuroprotective effects and remarkable therapeutic potential. PACAP activates several cellular pathways to exert its protective effects. Emerging evidence shows that PACAP can modify the levels and activity of cell cycle components involved in neurodegeneration to protect neurons from death. Cell cycle is a highly regulated process that controls the balance between proliferation, differentiation and death of every cell in the body. Aberrant expression and function of components of the cell cycle machinery have been linked to neurodegenerative diseases, in which different types of neuronal cells become dysfunctional and die in response to toxic insults. Since neurons are postmitotic cells, re-entry into the cell cycle has been shown to be pathological and contributes to the process of neurodegeneration. Moreover, an increasing number of studies highlight the importance of the role of cell cycle components outside the cell cycle and their involvement in neurodegenerative disorders. Here, we discuss the pleiotropic effects of PACAP on cell cycle machinery and the implication for the treatment of neurodegenerative diseases.

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with diverse actions, including strong neurotrophic and neuroprotective effects. The aim of our present review is to provide a summary of the different approaches how in vivo neuroprotective effects can be achieved, emphasizing the potential translational values for future therapeutic applications. In the central nervous system, PACAP has been shown to have in vivo protective effects in models of cerebral ischemia, Parkinson's and Alzheimer's disease, Huntington chorea, traumatic brain and spinal cord injury and different retinal pathologies. PACAP passes through the bloodbrain barrier and therefore, systemic administration can affect the nervous system and lead to neuroprotective effects. This review summarizes results obtained in neuronal injury studies via local, such as intracerebral, intrathecal, intracerebroventricular, intravitreal and systemic treatments, such as intravenous, intraperitoneal and subcutaneous administration of PACAP. A few other options are summarized, like intranasal and eye drops treatments, as well as difficulties and side effects of different treatments are also discussed.

The realization of the importance of growth factors in adult CNS led to several studies investigating their roles in neuropsychiatric disorders. Based on the observations that chronic stress decreases brain-derived neurotrophic factor (BDNF) and antidepressant treatments reverse BDNF to normal levels, "neurotrophic hypothesis of depression" was proposed. Subsequent studies found that several other growth factors, including fibroblast growth factor (FGF), vascular endothelial growth factor, nerve growth factor were also decreased by chronic stress. Growth factors promote stem cell survival, angiogenesis and neurogenesis in addition to having anti-apoptotic and anti-inflammatory effects, all of which make them potential drug candidates as neuroprotective or neurorestorative agents. Indeed, certain peptides have consistently been shown to improve stroke outcome in experimental models of cerebral ischemia. Recent developments in nanotechnology appear promising in overcoming the blood-brain barrier and in delivering sufficient amounts of these large peptides to the brain after systemic administration. In addition to the translational potential resulting from application of nanotechnical approaches for delivering these large peptide growth factors, recent success obtained with small molecule and peptide antagonists of calcitonin gene-related peptide has created renewed enthusiasm to elucidate the role of neuropeptides in migraine headache, one of the most common health problems in the world. In this review, we will first focus on the role of FGF2 in mood disorders as well as in ischemic stroke. We will also introduce the nanomedicines developed to efficiently deliver FGF2 to the brain. In the last section, we will explore roles of the neuropeptides in migraine and its acute and prophylactic treatment.

The term endozepines designates a family of astroglia-secreted proteins including the diazepambinding inhibitor (DBI) and its processing products, which have been originally isolated and characterized as endogenous ligands of benzodiazepine receptors. It is now clearly established that the octadecaneuropeptide ODN (DBI33-50), acting through the central-type benzodiazepine receptor or a metabotropic receptor, exerts important functions such as proconflict behavior, induction of anxiety, inhibition of pentobarbital-provoked sleep, decrease of water consumption and reduction of food intake. To mediate its effects, ODN regulates both glial cell and neuronal activities by acting on neurosteroid biosynthesis and/or neuropeptide expression. In addition, ODN stimulates astrocyte proliferation and protects both neurons and astrocytes from oxidative stress-induced cell death. The antiapoptotic effect of ODN on neural cells is mediated through activation of the ODN metabotropic receptor positively coupled to PKA, PKC and MAPK/ERK transduction pathways, which ultimately reduces the pro-apoptotic gene Bax and stimulates Bcl-2 expressions, and inhibits intracellular reactive oxygen species accumulation. The imbalance in favor of Bcl2 promotes mitochondria functions and blocks in turn caspases activation while at the same time, ODN also activates the endogenous antioxidant system i.e. glutathione biosynthesis, and expression and activities of antioxidant enzymes. In cultured astrocytes, DBI expression is up-regulated during moderate oxidative stress, and authentic ODN production is increased, suggesting that ODN may act as a paracrine factor protecting neighboring neurons. Taken together, the remarkable effect of ODN on the apoptotic cascade suggests that innovative ODN derivatives could potentially be useful for treatment of cerebral injuries involving oxidative stress and neurodegeneration.

Galanin-like peptide (GALP) is composed of 60 amino acid residues and its sequence is highly homologous across species. GALP is produced in the hypothalamic arcuate nucleus and has diverse physiological effects such as the regulation of feeding, energy metabolism, and reproductive behavior. GALP-containing neurons express leptin receptors and these neurons form networks in the hypothalamus that contain various peptides that regulate feeding behavior. Recent studies have revealed that GALP has a central anti-obesity action in addition to its role in food intake regulation. Furthermore, we have found that the respiratory quotient declines shortly after administration of GALP into the lateral ventricle. This suggests that lipid metabolism is accelerated by GALP administration, and identifies a new physiological action for this peptide. In this review article, we summarize our recent research focusing on the mechanism whereby GALP regulates feeding and energy metabolism. We concentrate on the mechanism of regulation of lipid metabolism in peripheral tissues via the autonomic nervous system and outline the effectiveness of the nasal administration of GALP and basic research towards its clinical application.

Background: Psoriasis is an autoimmune disease of the skin with lapsing episodes of hyperkeratosis, irritation and inflammation. Numerous methodologies and utilization of different antipsoriatic drugs with various activity methods and routes of administration have been investigated to treat this terrifying sickness. In any case, till date, there is no remedy for psoriasis because of the absence of an ideal carrier for effective and safe delivery of antipsoriatic drugs. Objective: Among the different methods of medications for psoriasis, in the greater part of patients, topical treatment is most commonly utilized. For topical formulations, utilization of conventional excipients could fill the need just to a restricted degree. With the revelation of more up to date biocompatible and biodegradable materials like phospholipids, and Novel drug delivery technologies like liposomes, solid lipid nanoparticles (SLNs), microemulsions, and nanoemulsions, the possibility to enhance the efficiency and safety of the topical products has expanded to a great extent. Understanding the topical delivery aspects and that of outlining and creating different carrier systems have been enhanced that got further novelty to this approach. Conclusion: Present review is an attempt to contemplate on psoriasis as far as improved comprehension of the dermal delivery perspectives and at present accessible treatment alternatives, significant preventions in psoriasis treatment, late advancements in the conveyance of different antipsoriatic drugs through novel colloidal drug transporters.

Background: Essential oils (EOs) and their volatile components (VCs) have varied biological and pharmacological activities, but low solubility and bioavailability hamper their applications, so that inclusion in cyclodextrins (CDs) is likely to improve their physicochemical properties and pharmacological effects. Objective: The authors conducted a systematic review to evaluate the biological activities and pharmacological applications of essential oils and their volatile components complexed with cyclodextrins. Methods: The search terms 'Cyxlodextrin', 'Inclusion Complex', 'Volatile oils', 'Essential oil' and 'Volatile components' were used to retrieve articles from the PUBMED, MEDLINE and SCOPUS databases. Results: A total of 38 articles were identified. A greater efficacy of EOs and their VCs complexed with different CDs types was found in in vitro and preclinical studies when compared to free forms in the various biological activities and animal models of the evaluated pharmacological tests. Conclusion: This review of selected studies showed that the use of CDs promotes greater solubility, bioavailability and efficacy of EOs and their VCs, thus indicating an interesting alternative for the biotechnological development of new therapeutic formulations.

Background: Candida albicans is a commensal and opportunistic fungus which is able to produce both local and systemic infections in immunocompromised patients. A correlation has been demonstrated between the resistance to conventional antifungal drugs and C. albicans ability to produce biofilms. Therefore, the potential of the organochalcogen compounds as antifungal therapy has been demonstrated. Method: In this work, we studied the effect of the organochalcogen compound (MeOPhSe)2 on both formation and the viability of the biofilm produced by C. albicans, at different stages of development. Biofilm formation and viability were determined by a metabolic assay based on the reduction of XTT assay. In addition, the morphology of the biofilm was observed using light microscopy. Results: A significant reduction was observed in both growth and biofilm formation by C. albicans, in a dependent manner of cell density. In the presence of 2 μM (MeOPhSe)2 it was observed an inhibition of 87, 72, 69 and 56 % in C. albicans growth, using cell densities of 104, 105, 106 and 107 cells/mL, respectively. C. albicans growth was inhibited >90 % in the presence of 10 μM (MeOPhSe)2 in all cell densities used. Also, (MeOPhSe)2 was found to be able to decrease the viability of the biofilm produced by C. albicans at different stages of development. This effect was more pronounced in early biofilms as compared to mature biofilms. Biofilms forming at 6 and 12 hours was inhibited ~80% in the presence of 10 μM (MeOPhSe)2. However, mature biofilms presented an inhibition of ~40 % in the presence of 10 μM (MeOPhSe)2. The analyses of the structure of the biofilm have shown a significant reduction in the number of both yeast and filamentous form after treatment with (MeOPhSe)2. In addition, the organochalcogen compound (MeOPhSe)2 did not modify the viability of Fibroblastic cells. Conclusion: Taken together, these results demonstrated the potential of the organochalcogen compound (MeOPhSe) 2 as a promising antifungal therapy.

Background: Alzheimer disease (AD) can be considered as the most common age related neurodegenerative disorder and also an important cause of death in elderly patients. A number of studies showed the correlation of this disease pathology with BACE1 inhibitor and it is also evident that BACE1 inhibitor can function as a very potent strategy in treating AD. Methods: In this present study, we aimed to prospect for novel plant-derived BACE1 inhibitors from Leea indica and to realise structural basis of their interactions and mechanisms using combined molecular docking and molecular dynamics based approaches. An extensive library of Leea indica plant derived molecule was compiled and computationally screened for inhibitory action against BACE1 by using virtual screening approaches. Furthermore, induced fit docking and classical molecular dynamics along with steered molecular dynamics simulations were employed to get insight of the binding mechanisms. Results: Two triterpenoids, ursolic acid and lupeol were identified through virtual screening; wherein, lupeol showed better binding free energy in MM/GBSA, MM/PBSA and MM/GBVI approaches. Furthermore classical and steered dynamics revealed the favourable hydrophobic interactions between the lupeol and the residues of flap or catalytic dyadof BACE1; however, ursolic acid showed disfavorable interactions with the BACE1. Conclusion: This study therefore unveiled the potent BACE1 inhibitor from a manually curated dataset of Leea indica molecules, which may provide a novel dimension of designing novel BACE1 inhibitors for AD therapy.

Background: Baicalin constitutes a natural bioactive flavonoid extracted from Scutellaria baicalensis Georgi that mediates bone formation. However, the biological functions of baicalin in cementoblasts remain unclear. The purpose of this study was to examine the effects of baicalin on osteogenic differentiation of human cementoblast (HCEM) cells. Methods: HCEM cells were cultured and treated with 0, 0.01, 0.1 or 1 μM baicalin. Alkaline phosphatase (ALP) and runt-related transcription factor 2 (Runx2) mRNA and protein levels were examined by real-time polymerase chain reaction and western blot analysis, respectively. Cell mineralization was assessed using Alizarin red staining. Glycogen synthase kinase-3 beta (GSK3β) phosphorylation was measured in 1 μM baicalin-treated HCEM cells with or without the Wnt signaling pathway inhibitor, DKK-1 using ELISA and western blotting. Results: The protein levels of ALP and Runx2 and the intensity of Alizarin red staining were enhanced by baicalin in a dose-dependent manner compared to that of the non-treated control. The ratio of phosphorylated to total GSK3β increased in the presence of baicalin but was reduced by the addition of DKK-1. Treatment of HCEMs with baicalin up-regulated mRNA levels of ALP and Runx2, which were reduced by DKK-1. In addition, the protein levels of ALP and Runx2, ALP activity, and calcium deposition were also enhanced by baicalin, and these parameters were inhibited by DKK-1. Conclusion: Baicalin enhanced osteogenic differentiation of HCEM cells through the Wnt/beta catenin signaling pathway which may be useful for periodontal tissue regeneration.